Antifoam material



Patented Apr. 14, 1953 stars ANTIFOAM MATERIAL Emery I. Valko, Mountain Lakes, N. J and Jonas Kamlet, New York, N. Y., assignors to E. F. Drew & (30., Inc., New York, N. Y., a corporation of Delaware No Drawing. Original application October 27, 1948, Serial No. 56,912. Divided and this application September 7, 1949, Serial No. 114,454

4 Claims. (Cl. 252358)- conditions small amounts of impurities inthe.

water havea tendency to cause foaming in the boilers and the carrying over of liquid particles which enter other apparatus and cause detrimental effects. This difiiculty has been known for some time and various attempts to correct the tendency to foam have been made. In the prior art, it was proposed to add relatively small amounts of various compounds in order to reduce foaming and such additions have been of some value for this purpose. Some of such compounds were not compatible with other substances used in the treatment of water for use in boilers. Also,- a relatively large quantity of such compounds were necessary in order to give effective results and some difilculties in using them arose.

The present invention is intended and adapted to overcome the difiiculties and disadvantages inherent in the prior art, it being among the objects of the present invention to provide a composition adapted for introduction into aqueous media. such as in high pressure boilers, which is compatible with other substances used in treating water and which is highly eiiective in reducing or eliminating foaming.

It is also among the objects of the present invention to provide a composition for treatment of aqueous media which may be readily and cheaply produced from easily available raw materials and which is stable under the conditions of use.

The present invention is based upon the conception that compounds of a certain type are eminently suitable for use in preventing or elimthe present invention have the following structural formula:

RNHCO B it wherein X may be alkyl, aryl, aralkyl, homocyclic and heterocyclic, and in which the two nitrogen atoms attached to said radical are on adjacent carbon atoms. R is a hydrocarbon radical having from 2 to 4 carbon atoms and R is a hydrocarbon radical having from 9 to 29 carbon atoms.

Among the radicals designated by the letter X are the following: ethylene, propylene, phenylene and substitution products thereof. The R groups are usually straight chain compounds but they may be branched chain, aryl or aralkyl.

The following are specific examples of the operation of the present invention.

Example 1 270 parts by weight of commercial stearic acid are mixed with 52 parts by weight of diethylene- Y triamine, being in the molecular ratio of 2 to 1.

The mixture is agitated, a gentle stream of nitrogen is passed through the same and the mixture is heated over a period ranging from lhour to 1 hours, to a temperature of about 215 C. at atmospheric pressure.

during the heating up period h l a Then 2.5 parts by weight of diethylenetrlamrne are added to the reaction mass and the temperainating foaming when added to boiler waters or ture of 215 C. is maintained for about 1 hours under 'a pressure of about 5 mm. obtained by progressively decreasing the pressure in the systern. An additional amount of distillate is recovered from the reaction vessel during the vacuum heating. The reaction taking place is as follows:

NI-IzCHzCI-IzNI-ICHzCHzNI-Iz ZCmEsCOOH CHaCHzNHC 0 (3111335 C HrN The product contains three hydrophylic nirender the substance water-insoluble and thus A small amount oi distillate is removed from the reactingmixture effectively maintain the foam reducing properties of the compound.

An equivalent amount of such higher. carboxylic acids, as behenic, may replace stearic in the process...

Example 2 The compound of Example 1 is emulsified or dispersed for ready application to boiler. feed waters since the compound alone is water ina soluble. The following composition is made:

Pounds- Product of Example 1 4-8". Hydroxy acetic acid (70% aqueouss'o'lution) 4% Light lubricating mineral oil 20 Water 254;

The several constituents areatherouahlmmixedl: whereby a reaction takes place forming theby droxy acetate of the imidazoline. I'he- :lieht-tb=- medium lubricating fraction of the mineral oil renders the composition! moreliiuidi andistabi-iizes: the emulsion with the water.

The composition; ,3 whiehris quite fluid, is introduced into the feed water at the rate of 2 parts of the composition to 1,000,000 parts of the water. Because of the fluidity of the emulsion it is readily dispersed in the feed water and is quite effective .inlpreventing foamin a A reaction is conducted .in, -,the. samelmannen. as-vin. Example .:1,. suhstitutingior the. stearic. acid; lauric...a idn which may .basubstanti'allii hum-1: 13

may be admixed with ,.very.; smalllamourrtsmg concomitantifatty acids. .or;. coecnuiz 0.112;;

Examples 5 linsteadr-ofi-a single iatty acid; there-is :used as; starting material the-higher mi xed iatty-.aeids derived bysplitting. ofcoconut oil and, fractiom ating: the fattyaacids. The-fraction, containing acids-ofandr the higher .carbon'acids'are .used. This mixture is reacted in the ratio of 2. m01 with..1 mol. ofldiethylenetriamineas set forth in Example 1.

A composition containing-the product is as follows:

' Per cent Above product Water 80 Propylene glycol- V 3.25 Polyethylene glycolx300 mono -oleatea 1.75

The vmono-oleateacts as a dispersing or emulsitying agentiwhereby the'mixed imidazoline is; dispersed in the water. The-,propylene: glycol has the function offprovi'd'ing a' soft consistency to the resulting paste. The composition may then be applied to the feed water for boilers.

Example 6 A migtur e ,is made 0f,,. 1.., ,mol or stearic acid with-,1 moi-3 :01; diethylenetriaminei and the mixture is heatedto a temperature of about 215 C. until a reaction has taken place, whereby the im-idazoline ring formation takes place. While stillimaintaining the reaction temperature, 1 mol. 'of myristic acid is added and the reaction is continuediuntil th'e'acid has reacted and the acyl radical; thereof-'-= is; attached to the available nitrogen,

The product may be used as indicated for treatmentspi boilehzieetd waters.

Example 7 Acornposition is made of any of the above described imidazolines in the following proportions by weight;

Peri-cent.

Imid'azoline' p 13420 Coconut oii=soap-(50%-'soln.)1; "I..- Na0I-I *(85% solh.) I{ 53 "Tannic acid; 4:20

Polyethylene glycol- (600 mol. wt.')-=monool'eate 3 .00 Water 74.50

The anni'ci..aci. forms,sOd1llm..t%Q1l tB.. i1ih., the. caustic soda and this is mixedwith the, moltenimidazoline whereby a complex is formedr Th cq plex is. emu s fi ciibrthe oahandmona:

ole 't nform a t e m l ien...wi ri' theyvater... .The; u e f he. two m lsi yin asentslgivesla...

better" emulsion than when only one such. een is p l d hecompqsit en int singed.

into. h feed: at r at herei l i. 1 part;

eof to 1 9 900 aris. iiwetene. q o asbeen; f'qun mpat le .withu ar usmater e nfl o ler' ateri ament. as -alginates; tannins and others wamel .8-1; 450 parts by weight of commercial stearijc I agid i;

"ismixed with 135' partsby; weight cliis o-propylenetriamine (representing a ratio of '2--mols'. acid to- 1-mo1'. amine-with-aslight excess oi; the latter) and heated first at atmospheric pressure and later under vacuum. The temperature is-bro'ught upsgradually- -from 150" to 240- andthenthe; heatingcontinues; under-vacuum, which gradin allyis-increased from i0 mm. toi=5;mn i. imer-,-

cury ;--for 1 /2" hours-at 2-15"-=G. The-water ofcohdensationliberated during thereaction correspondsto approximately 3-- mols.- per mol: airline.-

i d c e f maiiqn-nf n sie sl x hn dine of the following formula;

OH: Q Hi. I m QQ 1 CHN The-: p unds a dv com osi iens-orr-th p s:

ent. invention have; propertieswhich; render;- them; highly suitable, for application. to boiler; feed:

,waters.v Th y are extremely. efficient ineliminating foaming, even vwhen used in .small' quanti: t es. hey are. a y Qintr Q iQe i a e thaw-fi ter; d are mpati l i h v t er beiier water treat: e t -v A so he are ta le hiirth hiehiemr'.

.. .pe u o dnh e i, rs su ebeilers Thea are easily prepared by a simple process from readily available and comparatively cheap raw materials. No highly skilled workmen are necessary to operate the process and a simple apparatus is sufiicient. Duplication of the products in a series of batches is readily obtained.

The substances are adapted for use in various operations where water or aqueous solutions are so treated as to incidentally produce undesirable foam. For instance, in plants for the production of yeast in breweries and in similar operations, the course of fermentation often causes foaming and it is desired to reduce or eliminate the same. The present substances may be added to vats in which the fermentation takes place, in suitable amounts and at such intervals as will minimize or eliminate the foaming. The substances may also be added to the water before it enters the operation if this appears desirable or feasible. Similarly in other operations where the substances do not interfere with the reactions taking place, they may be added for the elimination of the foam.

Although the invention has been described setting forth several specific embodiments thereof, the invention is not limited thereto but various changes in the details may be made within the spirit of the invention. For instance in place of the fatty acids enumerated in the specific examples, other acids, either synthetic or natural, having from to 30 carbon atoms may be used in place thereof or in conjunction therewith. Single acids as well as mixtures of acids are suitable for the purpose. Among the acids which have been found satisfactory are those contained in the higher boiling fraction obtained from coconut oils. The amount of the imidazoline which may be used in boiler water may be varied over a wide range and it has been found that from .5 to 10 parts per million of feed water gives satisfactory results. Other emulsifying agents than those specifically named may be used, such as Turkey red oil, alkyl aryl sulphonates, alkylphenolpolyglycol ethers, and others, all of which have been described in the literature. In place of tannic or hydroxyacetic acid, other suitable acids may be used in conjunction with the imidazolines. The imidazolines may have added thereto alginic acid or an alkali metal phosphate.

We claim:

1. A composition suitable for the treatment of aqueous media to prevent foaming consisting essentially of a water dispersion of a compound having the following general formula:

in the form of its complex with an acid taken from the class consisting of hydroxyacetic and tannic.

2. A composition suitable for the treatment of aqueous media to prevent foaming consisting es-' sentially of a water dispersion of a compound having the following general formula:

RNHCOR CHzN C HZOHQNHC O C nHas CHzN C-CuHas HzN in the form of its complex with an acid taken from the class consisting of hydroxyacetic and tannic acid and containing alginates.

4. A composition suitable for the treatment of aqueous media to prevent foaming consisting essentially of a Water dispersion of a compound having the following general formula:

CHzCHzNHC O C "H35 C HzN C-CnHas HzN in the form of its complex with an acid taken from the class consisting of hydroxyacetic and tannic and containing a mixture of soap and poly-ethylene-glycol mono-cleats.

EMERY I. VALKO. JONAS KAMLET.

References Cited in the file of this patent UNITED STATES PATENTS Name Date Barber et al Oct. 11. 1949 Number 

1. A COMPOSITION SUITABLE FOR THE TREATMENT OF AQUEOUS MEDIA TO PREVENT FOAMING CONSISTING ESSENTIALLY OF A WATER DISPERSION OF A COMPOUND HAVING THE FOLLOWING GENERAL FORMULA: 